Skimming kraeusen from a lager - Home Brew Forums

Register Now!
Home Brew Forums > Home Brewing Beer > All Grain & Partial Mash Brewing > Skimming kraeusen from a lager

Reply
 
Thread Tools
Old 07-16-2008, 09:28 PM   #1
tinydancer
Recipes 
 
Jun 2008
Gibsonville, NC
Posts: 9


I'm reading Gregory Noonan's book, "New Brewing Lager Beer"... In it he advises than the kraeusen should be skimmed after high kraeusen to prevent it from settleing back into the beer, which could impart a "harshness" to the finished beer. I have not heard much about this technique/philosophy and was curious if any of you skim the kraeusen. If so, how is this done? With what tool/implement? Any thoughts?


 
Reply With Quote
Old 07-16-2008, 10:22 PM   #2
menschmaschine
 
menschmaschine's Avatar
Recipes 
 
Jun 2007
Delaware
Posts: 3,272
Liked 41 Times on 33 Posts


Not sure what page you're reading, but I think he means only in open fermentation. It's just the oxidized scum that can contribute harsh flavors to the beer. In closed fermentation, you don't need to worry about it because the kraeusen isn't exposed to oxygen.

 
Reply With Quote
Old 07-17-2008, 12:03 AM   #3
tinydancer
Recipes 
 
Jun 2008
Gibsonville, NC
Posts: 9

ok...well that might be the case then. I was reading the portion on "Late Kraeusen" on page 184. But what you're saying makes sense. As you said he may have been referring to open fermentation.

 
Reply With Quote
Old 07-17-2008, 02:55 AM   #4
JVD_X
HBT_LIFETIMESUPPORTER.png
 
JVD_X's Avatar
Recipes 
 
Jan 2008
Gainesville, Virginia
Posts: 1,478
Liked 4 Times on 4 Posts


The kraeusen carries volatile oils in it that when not removed with the head are carried back down into the beer when the kraeusen falls, potentially causing off-flavors. I always remove the kraeusen from the head of my lagers using a big spoon. It usually forms several times and for this reason simply racking off after the first kraeusen forms is not sufficient.
__________________
- JVD_X

 
Reply With Quote
Old 07-17-2008, 12:37 PM   #5
menschmaschine
 
menschmaschine's Avatar
Recipes 
 
Jun 2007
Delaware
Posts: 3,272
Liked 41 Times on 33 Posts


Quote:
Originally Posted by atarlecky View Post
The kraeusen carries volatile oils in it that when not removed with the head are carried back down into the beer when the kraeusen falls, potentially causing off-flavors. I always remove the kraeusen from the head of my lagers using a big spoon. It usually forms several times and for this reason simply racking off after the first kraeusen forms is not sufficient.
What is your source on this? "Volatile oils" are better known as essential oils. Where are these from, the hops? barley? Why would they cause harsh flavors? I would tend to disagree with skimming in closed fermentation unless you're trying to harvest yeast. The way Noonan explains it (pg 180, I think?) makes sense to me. Also, the risk of contamination alone is enough to sway me. I've never skimmed and I don't notice any harsh flavors in my lagers.

 
Reply With Quote
Old 07-17-2008, 05:07 PM   #6
springer
 
springer's Avatar
Recipes 
 
Feb 2008
Wappingers falls NY
Posts: 4,743
Liked 24 Times on 22 Posts


and how would you do this if your using a Carboy?My lager didnt even make all that much kraeusen compaired to the ales I make
__________________
'The taxpayer: That's someone who works for the federal government but doesn't have to take the civil service examination.'- Ronald Reagan

 
Reply With Quote
Old 07-17-2008, 06:32 PM   #7
nathan
 
nathan's Avatar
Recipes 
 
Apr 2008
NC
Posts: 945
Liked 4 Times on 4 Posts


you could ferment a 5.5 batch in a standard carboy (5 gal) so it's full to the neck, and put on a blowoff tube that fits inside the neck. It'll blow off into your bucket and be unable to fall back in.

I don't worry about it, though. I get stuff sticking to the walls of the 7gal carboy, and I leave it there.
__________________
______________________________________
beer.

 
Reply With Quote
Old 07-18-2008, 02:16 PM   #8
korndog
 
korndog's Avatar
Recipes 
 
Nov 2007
westlake village, ca
Posts: 1,119
Liked 8 Times on 6 Posts


Quote:
Originally Posted by nathan View Post
you could ferment a 5.5 batch in a standard carboy (5 gal) so it's full to the neck, and put on a blowoff tube that fits inside the neck. It'll blow off into your bucket and be unable to fall back in.
Sounds simple and elegant. Any drawback?
__________________
"..can the human soul be glimpsed through a microscope? Maybe, but you'd definitely need one of those very good ones with two eyepieces."


Twitter: LarryKonis

 
Reply With Quote
Old 07-18-2008, 05:35 PM   #9
hughmac
Recipes 
 
Jul 2008
Posts: 27
Liked 1 Times on 1 Posts


Quote:
Originally Posted by korndog View Post
Sounds simple and elegant. Any drawback?
Well, the extra bucket takes up some space in your fridge, or wherever you're fermenting. I've had it fill up a too-small container (a glass) that I was doing this into and spill all over the bottom of the fridge.

Works great though!

One time I sucked up the krausen with a sterilized racking tube attached to my shopvac. That was WAY to much work, but kind of fun. Although that batch of IPA was particularly good, who knows if it was related? Now I generally just do the blowoff hose with 5.25gal batches and sacrifice a beer or so worth of juice in the name of spewing out the krausen.
__________________
*
Schuylkill River Brewing Co.
Taps: Smack-you Ginger Ale
Bottles: DUSTY
Conditioning: Nada
Secondary: Oddman Ordinary
Primary: Nada
On-Deck: Maibock? Schwartzbier?

*

 
Reply With Quote
Old 07-18-2008, 06:13 PM   #10
JVD_X
HBT_LIFETIMESUPPORTER.png
 
JVD_X's Avatar
Recipes 
 
Jan 2008
Gainesville, Virginia
Posts: 1,478
Liked 4 Times on 4 Posts


Quote:
Originally Posted by menschmaschine View Post
What is your source on this? "Volatile oils" are better known as essential oils. Where are these from, the hops? barley? Why would they cause harsh flavors? I would tend to disagree with skimming in closed fermentation unless you're trying to harvest yeast. The way Noonan explains it (pg 180, I think?) makes sense to me. Also, the risk of contamination alone is enough to sway me. I've never skimmed and I don't notice any harsh flavors in my lagers.
That is also in noonans book... it is from the trub and fermentation. Page 142-155. 1986 edition. He indicates that not removing the first dirty krauesen it will allow it to fall back into the beer affecting stability. Oh - and I use a semi-open fermentation (it has a lid that just sits on top) not closed fermentation.

In any case - I think the chance of infection is over-rated. I regularly leave my unpitched wort in the freezer at 50 degrees for a week without any issues (just because of timing). I also skim my lagers with no issues.
__________________
- JVD_X

 
Reply With Quote
Reply
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Yeast washing vs. yeast harvesting (kraeusen skimming) Dogslovebeer General Techniques 14 05-30-2013 06:05 PM
Post lager fermentation , skimming low krausen. GilaMinumBeer General Techniques 2 09-03-2008 06:23 PM
Skimming WormBoy All Grain & Partial Mash Brewing 23 06-12-2007 07:19 PM
Skimming the Kraeusen Baron von BeeGee General Techniques 7 04-25-2006 07:23 PM
skimming off scum? mrkeeg Mead Forum 2 12-13-2005 03:46 AM


Forum Jump